Law 9 - Ball In and Out of Play

The ball is out of play when (a) it has completely crossed the goal line or touchline, whether on the ground or in the air, or (b) the game has been stopped by the referee. The ball continues to be in play even though it comes in contact with the field outlines, the goal structure in the field of play, the flags or the referee. On fields that use football goalposts or other devices to support soccer goals, the referee shall declare the ball out of play when it contacts the additional structure.